A wiring harness multi-channel CAN line conduction loop test circuit device

Abstract

The utility model discloses a wiring harness multi-channel CAN line conduction loop test circuit device, comprising a signal generator for sending a test signal and a signal receiver for receiving the test signal, wherein the signal generator is connected to the access end of the wiring harness assembly to be tested, and the signal receiver is connected to the access end of the wiring harness assembly to be tested; the signal generator is provided with a plurality of first indicator lights, which can light up when the signal generator sends the test signal, and the signal receiver is provided with a plurality of second indicator lights, which can light up when the signal receiver receives the test signal, wherein when all the first indicator lights and all the second indicator lights are all lit, the multi-channel CAN line conduction loop test of the wiring harness assembly to be tested is passed. The utility model has low cost, simple equipment, flexible and convenient use, low error rate, and is suitable for small batch and multi-type wiring harness production scenarios.

Description

Technical Field

[0001] The utility model relates to a wiring harness conduction test, in particular to a wiring harness multi-channel CAN line conduction loop test circuit device. Background Art

[0002] In the wiring harness assembly product, a CAN bus system is composed of two groups of differential signal transmission wires. One group of differential signal wires includes ≥2 single wires, which are twisted together. The two twisted differential signal transmission wires can go to 2 or more signal nodes (including controllers, actuators, power supplies, etc.). The two differential transmission signal lines transmit signals CAN-H and CAN-L respectively. All nodes on the CAN bus system can be connected to these two differential signal transmission lines for communication. The connection method is: CAN-H connects to CAN-H, and CAN-L connects to CAN-L.

[0003] At present, complex machines and equipment, including aircraft, automobiles, heavy machinery and equipment, robots, etc., have more and more integrated electrical functions, the electrical systems are becoming more and more complex, and the information interaction between controllers is becoming more and more complex. As a result, there is often more than one set of CAN networks in the wiring harness assembly products. Sometimes they are distinguished by speed, with common speeds of 125kbps, 250 kbps, 500 kbps and 1Mbps; sometimes they are distinguished by functional systems, including safety system CAN, power system CAN, comfort system CAN, etc. One of the prerequisites for normal information interaction of complex machines and equipment is the reliable and correct operation of the CAN network. Therefore, in the process of wiring harness production, functional testing and performance testing of the wire connection of the CAN bus system are particularly important, which can avoid the problem of wire harness assembly product rework caused by CAN wire connection errors, and inspection and rework caused by abnormal functions of wire harness assembly products after installation.

[0004] In the production of wiring harness assembly products, the common methods for checking the CAN bus system are as follows:

[0005] 1. Use a professional wiring harness continuity tester to test the wire continuity to check whether there are problems such as wrong circuit, short circuit, open circuit, etc.;

[0006] 2. Manually use multimeter and other instruments to test the continuity of the wires to check whether there are any problems such as wrong circuits, short circuits, and open circuits.

[0007] The existing technologies have the following problems:

[0008] 1. Professional wiring harness continuity test bench:

[0009] I. High price. The price of professional wiring harness continuity test bench equipment is generally more than 10,000 yuan. If there are many connectors to be tested, the price can reach millions. And the copper parts of the matching connectors of the wiring harness connectors need to be processed, and this expense cannot be ignored;

[0010] Ⅱ. The equipment is huge and the debugging is complicated. The metal terminals between the connector copper parts need to be connected with wires, and then the connectors and the connector metal terminals are numbered one by one and entered into the equipment. Equipment debugging requires professionals to complete and takes a long time;

[0011] III. It is not flexible enough in use. The equipment can only be inspected according to pre-set parameters, and its application scope is relatively limited to mass production of wiring harnesses;

[0012] VI. Unable to detect the signal transmission quality of the CAN line.

[0013] 2. Manual inspection using a multimeter:

[0014] I. Low efficiency, manual inspection requires inspection of each wire one by one;

[0015] Ⅱ. The error rate is high, and the inspectors are required to have high skills, proficiency in the operation process, and high sense of responsibility. Otherwise, misjudgment and missed inspections are likely to occur;

[0016] III. Unable to detect the signal transmission quality of the CAN line. Utility Model Content

[0017] In order to solve the defects of the above-mentioned prior art, the utility model provides a wiring harness multi-channel CAN line conduction loop test circuit device. The utility model has low cost, simple equipment, flexible and convenient use, low error rate, and is suitable for small batch and multi-variety wiring harness production scenarios.

[0018] In order to achieve the above technical purpose, the utility model adopts the following technical scheme: a wiring harness multi-channel CAN line conduction loop test circuit device, comprising a signal generator and a signal receiver, the signal generator is connected to the input end of the wiring harness assembly to be tested, and the signal receiver is connected to the output end of the wiring harness assembly to be tested;

[0019] The signal generator sends out a test signal, and the signal receiver receives the test signal; the signal generator is provided with a plurality of first indicator lights, which can light up when the signal generator sends out the test signal, and the signal receiver is provided with a plurality of second indicator lights, which can light up when the signal receiver receives the test signal, wherein, when all of the first indicator lights and all of the second indicator lights are fully lit, the multi-channel CAN line conduction loop test of the wiring harness assembly to be tested is passed.

[0020] Furthermore, the number of the signal generators is the same as the number of CAN assembly systems of the wiring harness assembly to be tested, and the number of the signal receivers is the same as the number of nodes to be tested of the wiring harness assembly to be tested.

[0021] Furthermore, the test signal is a PWM wave.

[0022] Further, the test signal corresponds one-to-one to the PIN bit of the signal generator, and the test signal corresponds one-to-one to the PIN bit of the signal receiver.

[0023] Furthermore, the first indicator light and the second indicator light are both LED lights.

[0024] Furthermore, the LED lamp adopts model XL-2020RGBC-SK6812B.

[0025] Furthermore, the signal generator adopts model VC2060H or model SDG1022X.

[0026] Further, the signal generator is connected to the master node end of the wiring harness assembly to be tested, and the signal receiver is connected to the slave node end of the wiring harness assembly to be tested.

[0027] In summary, the utility model has achieved the following technical effects:

[0028] The utility model uses an independent signal generator and a signal receiver to perform a conduction test, which has a flexible combination, a small device size and a low cost;

[0029] The utility model uses an indicator light to replace an expensive screen, compresses the volume of the entire product, and reduces the cost;

[0030] The utility model uses a signal generator and a signal receiver to perform signal detection. The signal receiver compares the signal with a pre-stored test signal for signal consistency. The detection will be passed only when the signals are consistent or the error is within the program allowable range. This test method can avoid the problem of traditional simple conduction test and the inability to identify the short circuit between CAN wires inside the wiring harness. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of a wiring harness multi-channel CAN line conduction loop test circuit diagram provided by an embodiment of the utility model;

[0032] Figure 2 It is a flow chart of the continuity loop test circuit. DETAILED DESCRIPTION

[0033] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0034] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0037] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature. Example

[0039] like Figure 1 As shown, a wiring harness multi-channel CAN line conduction loop test circuit device includes a signal generator and a signal receiver, wherein the signal generator is connected to the input end of the wiring harness assembly to be tested, and the signal receiver is connected to the output end of the wiring harness assembly to be tested, so that the signal is transmitted from the signal generator to the signal receiver through the wiring harness assembly to be tested, and the signal transmission is completed, so that the signal transmission is judged to be correct by whether the signal receiver receives the signal, so as to prove whether the wiring harness assembly to be tested is connected correctly.

[0040] The signal generator sends out a test signal, and the signal receiver receives the test signal; the signal generator is provided with a plurality of first indicator lights, which can light up when the signal generator sends out the test signal, and the signal receiver is provided with a plurality of second indicator lights, which can light up when the signal receiver receives the test signal, wherein, when all of the first indicator lights and all of the second indicator lights are fully lit, the multi-channel CAN line conduction loop test of the wiring harness assembly to be tested is passed.

[0041] The number of the signal generators is the same as the number of CAN assembly systems of the wiring harness assembly to be tested, and the number of the signal receivers is the same as the number of nodes to be tested of the wiring harness assembly to be tested.

[0042] The test signal may be a PWM wave, a sine wave, etc. In this embodiment, the test signal is a PWM wave, the PWM waves are numbered one by one, the test signal corresponds one by one to the PIN bit of the signal generator, and the test signal corresponds one by one to the PIN bit of the signal receiver.

[0043] like Figure 1 As shown, the signal generator is connected to the master node end of the wiring harness assembly to be tested, and the signal receiver is connected to the slave node end of the wiring harness assembly to be tested, that is, the signal generator is located at the master node, the signal receiver is located at the slave node, and the wiring harness assembly to be tested is connected between the signal generator and the signal receiver. In this embodiment, the PWM waves output by the 4 PIN positions of the signal generator are numbered S1-H, S1-L, S2-H, and S2-L, respectively, and the 4 PIN positions of the signal receiver receive the waveforms numbered S1-H, S1-L, S2-H, and S2-L, respectively, and store the waveforms. Branch harness 1-branch harness n represent node harnesses on the CAN bus system, and each branch harness has CAN-H and CAN-L transmission signals, and the transmission signals of each branch harness are represented by SH and SL.

[0044] The first indicator light and the second indicator light are LED lights, which are arranged on the panel of the signal generator or the signal receiver to indicate whether a signal is sent or received, and one PIN position corresponds to one indicator light. The utility model uses an indicator light to replace the original screen, the screen is expensive, and the indicator light is cheap, so the cost of the utility model product is low, and the indicator light is a common LED light in the market, which is convenient to select and replace.

[0045] The signal generator of the utility model adopts the common models on the market, such as VC2060H of Shengli Instruments, SDG1022X of Dingyang, etc. The signal receiver adopts the common oscilloscope on the market. The signal generator will detect the received signal, including waveform, frequency, amplitude, duty cycle, etc. This technology is widely used in the field of LED control. The common XL-2020RGBC-SK6812B lamp beads can be used. The data latch circuit and data shaping processing circuit are integrated inside. When the signal received by the LED lamp bead is seriously distorted, the LED built-in chip will not control the LED to emit light.

[0046] Working principle, such as Figure 2 As shown:

[0047] First, determine how many CAN bus systems there are in the wiring harness assembly to be tested, and confirm the connection relationship of each CAN bus system to be tested, including the connector model and PIN position. This step is only required when the product is tested for the first time or there are changes;

[0048] Since the wiring harness assembly products involve various types of connectors, such as the 776932-3, 2209477-1, 2209477-2 and other types of connectors used by our company, after determining the connector model to be used, confirm the hole position information and establish the connection relationship of the tested CAN bus system, so as to connect the wires correctly;

[0049] 2. The signal generator sets the output signal waveform and numbers the waveform, such as S1-H, S1-L, S2-H, S2-L, etc., and matches the waveform with the numbered PIN position one by one; the signal receiver enters the S1-H, S1-L, S2-H, S2-L waveform and stores it; this step is only required for the first debugging of the device;

[0050] 3. According to the connection relationship of the CAN bus system determined in step 1, connect the wires, and also connect the power supply of the signal generator and signal receiver;

[0051] 4. Turn on the power of the signal generator and the signal receiver. The signal generator sends out a waveform signal. At this time, the first indicator light is on. If the corresponding PIN position of the signal receiver receives the correct waveform signal, the second indicator light is on. When all LEDs are on, it proves that the multi-channel CAN line conduction loop test of the wiring harness assembly product has passed, and the product label is printed; if a short circuit, open circuit or wrong circuit problem occurs, the test fails, and the wiring harness assembly product needs to be returned for repair;

[0052] 5. Repeat steps 3 and 4 until the testing of all wiring harness assembly products in the batch is completed.

[0053] The utility model generates a specific test signal at a signal generator of a master node and outputs it from a numbered PIN position. At this time, a corresponding LED on the signal generator lights up and is transmitted to a specific PIN position of a signal receiver at a slave node through a CAN line loop under test. The signal receiver compares the signal with a pre-stored test signal for signal consistency, that is, the signal generator detects the received signal, including waveform, frequency, amplitude, duty cycle, etc. When the signals are consistent or the error is within the allowable range of the program, the LED on the signal receiver lights up; if all the LEDs light up normally, the multi-channel CAN line conduction loop test of the wiring harness assembly product passes.

[0054] The product of the utility model can be used to economically and conveniently identify whether the CAN bus system wire has a fault in advance before the wiring harness assembly product is assembled on the vehicle / machine, thereby avoiding damage to electrical components and rework of the wiring harness.

[0055] If there is a fault, the symptoms are as follows:

[0056] 1. The wire is broken or wrong. Since the test signal cannot be transmitted to the signal receiver, the LED on the signal receiver is not lit;

[0057] 2. If the CAN lines are short-circuited, the signals between them will be interfered and deformed, and the LED on the signal receiver will not light up.

[0058] The product of the utility model is cheap, and only one signal generator and several receiving modules are needed for a CAN bus system; the connector can use a ready-made mating end connector, and there is no need to additionally process the mating connector copper parts of the wiring harness connector; the equipment is simple and the debugging is also simple, and the module can be powered on after the wiring is completed, which saves time and effort; it is flexible to use, and when producing different wiring harnesses, one CAN bus system corresponds to one signal generator and several receiving modules, which are flexibly matched and do not need repeated debugging; the error rate is low, and the use of the signal generator and the receiving module can avoid the problems of misjudgment and missed detection caused by manual detection; the signal transmission quality of the CAN line can be detected, and when the signal sent by the signal generator is transmitted to the receiver end, the receiver can detect the signal quality.

[0059] The above description is only a preferred implementation mode of the present invention, and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are within the scope of the technical solution of the present invention.

Claims

1. A wiring harness multi-channel CAN line conduction loop test circuit device, characterized in that: It includes a signal generator for sending a test signal and a signal receiver for receiving the test signal, wherein the signal generator is connected to the input end of the wiring harness assembly to be tested, and the signal receiver is connected to the output end of the wiring harness assembly to be tested; The signal generator is provided with a plurality of first indicator lights, which can light up when the signal generator sends out the test signal; the signal receiver is provided with a plurality of second indicator lights, which can light up when the signal receiver receives the test signal; wherein, when all of the first indicator lights and all of the second indicator lights are fully lit, the multi-channel CAN line conduction loop test of the wiring harness assembly to be tested passes.

2. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 1, characterized in that: The number of the signal generators is the same as the number of CAN assembly systems of the wiring harness assembly to be tested.

3. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 1, characterized in that: The number of the signal receivers is the same as the number of nodes to be tested of the wiring harness assembly to be tested.

4. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 1, characterized in that: The test signal is a PWM wave.

5. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 1, characterized in that: The test signal corresponds to the PIN bit of the signal generator one by one, and the test signal corresponds to the PIN bit of the signal receiver one by one.

6. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 1, characterized in that: The first indicator light and the second indicator light are both LED lights.

7. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 6, characterized in that: The LED lamp adopts model XL-2020RGBC-SK6812B.

8. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 1, characterized in that: The signal generator adopts model VC2060H or model SDG1022X.

9. A wiring harness multi-channel CAN line conduction loop test circuit device according to claim 1, characterized in that: The signal generator is connected to the master node end of the wiring harness assembly to be tested, and the signal receiver is connected to the slave node end of the wiring harness assembly to be tested.

Images